The present disclosure relates to a touch panel and a touch screen apparatus including the same.
A touch screen apparatus such as a touch screen, a touch pad, or the like, which is an input apparatus attached to a display apparatus to provide an intuitive input method to a user, has recently been widely used in various electronic devices such as a cellular phone, a personal digital assistant (PDA), a navigation device, or the like. Particularly, as the demand for smart phones has recently increased, as a touch screen apparatus capable of providing various input methods in a limited form factor, usage of the touch screen has been increasing day by day.
A touch screen used in a portable device may be mainly divided into a resistive type touch screen and a capacitive type touch screen according to a method of sensing a touch input. Here, the capacitive type touch screen has advantages in that it has a relatively long lifespan and may easily implement various input methods and gestures, such that the use thereof has increased consistently. Particularly, the capacitive type touch screen may more easily implement a multi-touch interface as compared to the resistive type touch screen, such that it is widely used in devices such as a smart phone, and the like.
The capacitive type touch screen includes a plurality of electrodes having a predetermined pattern and defining a plurality of nodes at which a change in capacitance is generated by a touch input. At the plurality of nodes distributed on a two-dimensional plane, a change in self-capacitance or mutual-capacitance is generated by the touch input. A coordinate of the touch input may be calculated by applying a weighted average method, or the like, to the change in the capacitance generated at the plurality of nodes.
In a touch panel according to the related art, generally, a sensing electrode recognizing touch is formed of indium tin oxide (ITO). However, since indium is a rare earth metal, ITO is expensive, such that price competitiveness may be low, and indium is expected to be depleted within the next decade, such that indium may not be sufficiently supplied. Due to the above-mentioned reasons, research into a method of forming an electrode using an opaque conductor thin line has been conducted. The electrode formed of a conductive thin line such as a metal has advantages in that electric conductivity is significantly excellent as compared to an electrode formed of ITO or a conductive polymer and the conductive thin line may be sufficiently supplied.
However, unlike an ITO electrode having a predetermined area, since the electrode formed of the conductor thin line is formed of a thin line, the electrode may be vulnerable to noise introduced through a contact object and a liquid crystal display (LCD) noise.